Merge branch 'akpm' (updates from Andrew Morton)

Merge first patch-bomb from Andrew Morton:
 - various misc bits
 - I'm been patchmonkeying ocfs2 for a while, as Joel and Mark have been
   distracted.  There has been quite a bit of activity.
 - About half the MM queue
 - Some backlight bits
 - Various lib/ updates
 - checkpatch updates
 - zillions more little rtc patches
 - ptrace
 - signals
 - exec
 - procfs
 - rapidio
 - nbd
 - aoe
 - pps
 - memstick
 - tools/testing/selftests updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (445 commits)
  tools/testing/selftests: don't assume the x bit is set on scripts
  selftests: add .gitignore for kcmp
  selftests: fix clean target in kcmp Makefile
  selftests: add .gitignore for vm
  selftests: add hugetlbfstest
  self-test: fix make clean
  selftests: exit 1 on failure
  kernel/resource.c: remove the unneeded assignment in function __find_resource
  aio: fix wrong comment in aio_complete()
  drivers/w1/slaves/w1_ds2408.c: add magic sequence to disable P0 test mode
  drivers/memstick/host/r592.c: convert to module_pci_driver
  drivers/memstick/host/jmb38x_ms: convert to module_pci_driver
  pps-gpio: add device-tree binding and support
  drivers/pps/clients/pps-gpio.c: convert to module_platform_driver
  drivers/pps/clients/pps-gpio.c: convert to devm_* helpers
  drivers/parport/share.c: use kzalloc
  Documentation/accounting/getdelays.c: avoid strncpy in accounting tool
  aoe: update internal version number to v83
  aoe: update copyright date
  aoe: perform I/O completions in parallel
  ...

1 files changed, 30 insertions, 0 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 6b4a79f4ad1d..94e94bd11aae 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -495,6 +495,35 @@ static int nfs_release_page(struct page *page, gfp_t gfp)
         return nfs_fscache_release_page(page, gfp);
 }
 
+static void nfs_check_dirty_writeback(struct page *page,
+                                bool *dirty, bool *writeback)
+{
+        struct nfs_inode *nfsi;
+        struct address_space *mapping = page_file_mapping(page);
+
+        if (!mapping || PageSwapCache(page))
+                return;
+
+        /*
+         * Check if an unstable page is currently being committed and
+         * if so, have the VM treat it as if the page is under writeback
+         * so it will not block due to pages that will shortly be freeable.
+         */
+        nfsi = NFS_I(mapping->host);
+        if (test_bit(NFS_INO_COMMIT, &nfsi->flags)) {
+                *writeback = true;
+                return;
+        }
+
+        /*
+         * If PagePrivate() is set, then the page is not freeable and as the
+         * inode is not being committed, it's not going to be cleaned in the
+         * near future so treat it as dirty
+         */
+        if (PagePrivate(page))
+                *dirty = true;
+}
+
 /*
  * Attempt to clear the private state associated with a page when an error
  * occurs that requires the cached contents of an inode to be written back or
@@ -542,6 +571,7 @@ const struct address_space_operations nfs_file_aops = {
         .direct_IO = nfs_direct_IO,
         .migratepage = nfs_migrate_page,
         .launder_page = nfs_launder_page,
+        .is_dirty_writeback = nfs_check_dirty_writeback,
         .error_remove_page = generic_error_remove_page,
 #ifdef CONFIG_NFS_SWAP
         .swap_activate = nfs_swap_activate,